I brought a lot of people into the Perl camp a dozen years ago by answering questions in comp.unix.questions
with both a shell answer and a Perl answer. The Perl answer was almost always shorter and easier to read, and almost always faster as well.
Perhaps you can do the same. Say "here's how to solve that in $LANGUAGE_X, but the Perl solution looks like this...". Do it enough times, they'll get the hint.
These days, the big winner seems to be the CPAN. So if you're in some $LANGUAGE_X design meeting, and someone mentions some basic task, just mutter "you know, I bet there's a freely available CPAN module for that part of the problem". Even if there isn't, they'll eventually get the hint.
-- Randal L. Schwartz, Perl hacker
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